During a phacoemulsification (“phaco”) procedure, a needle of an ultrasound handpiece is placed within the capsular bag of an eye to emulsify the cataractic lens. The emulsified lens is removed from the eye and an intraocular lens (“IOL”) is implanted. Ultrasound handpieces are driven by piezoelectric crystals or magnetostrictive drivers. Energy is applied to the piezoelectric crystals to vibrate the crystals to generate ultrasound energy, which is then transmitted through the needle of the handpiece into the cataractic lens. There are several theories as to how the cataractic lens is emulsified. One school of thought is that the ultrasound vibration causes cavitation, which in turn emulsifies the lens. Another school of thought is that the lens is emulsified by mere mechanical breakdown. Also, another school of thought is that it is a combination of cavitation and mechanical breakdown that emulsifies the cataractic lens. Despite these theories, there are several limitation placed on ultrasound handpieces when employing piezoelectric crystals. First, before each use the handpiece must be tuned, thereby lengthening the time of the procedure. Second, handpieces comprising piezoelectric crystals generate significant heat during use that may cause tissue damage. Third, the crystals add a significant amount of weight to the handpieces making them heavy and cumbersome to use and can cause fatigue for the doctors using such handpieces.
Based upon the foregoing, it would be advantageous to have a handpiece that is lighter, does not require tuning prior to use, and does not generate tissue damaging heat.